IntelliSnap - Frequently Asked Questions - Windows File System iDataAgent

How does the IntelliSnap backup operation work?

When you run a IntelliSnap backup operation, the Commvault software performs the operations listed below in the following sequence of events:

Create Snapshot on the Source

This event includes the following operations:

1. Device detection based on subclient content.

   This operation gathers information from local volume managers, multipath devices and physical disks (including partitions). For example, information on UUIDs is retrieved from a local volume manager.

2. Take snapshot of detected devices

   This operation invokes the snapshot functions from the file server and creates the snapshot. Once created, Commvault records the snapshot in the CommServe database along with metadata, which includes information about local volume managers, multipaths and physical disks.

Mount Snapshot on the Proxy

This event includes the following operations:

1. Map LUNs to the MediaAgent

   This operation invokes the file server functions to map clone devices to the proxy MediaAgent.

2. Recreate Storage Hierarchy

   Based on the metadata collected during device detection and snapshot creation, Commvault recreates the storage hierarchy as follows:

   • Devices are rescanned at the operating system level in order to allow the proxy to see the snapshot LUNs.

   • For each device detected on the source, Commvault checks the partitions to determine if the device is accessible or if it is a multipath device. If it is a multipath device, then the operation fails as partitions on multipath are not supported. However, if it is not a multipath device, then the software will keep parsing the device name to retrieve the partition information.

     When a partition number is detected, it is appended to the device name of the LUN. If no partition number is found, the full device name is used.

   • If required, the hierarchy of the local volume manager is recreated based on the metadata collected during device detection and snapshot creation.

   • File systems (LUNs and multipath disks) are mounted on the detected devices. Logical volumes are mounted in the case of logical volume managers.

   • Index is created and the software moves the data to the media.

What provisioning policies can I use?

Provisioning Policies are optional to use. During the creation of the secondary snapshot copy, the following Provisioning Policies are automatically created and available for selection in the CommCell Console:

• SnapProtect_RAID-DP

• SnapProtect_Dedupe

• SnapProtect_Mirror_Destination

If you need to create your own provisioning policy, ensure it is defined with the following naming convention in the OCUM server:

SnapProtect_<provisioning_policy_name>

where "SnapProtect_" is the prefix required for the provisioning policy to be available in the IntelliSnap software.

What happens when a vault or a mirror copy is created?

During an Auxiliary Copy job, a new dataset is created or an existing dataset is modified with new data members, as explained in the following flow of events:

1. When the IntelliSnap software assigns data to the service catalogue, a new baseline transfer may have started in the OnCommand Unified Manager (OCUM) server.

2. The Auxiliary Copy job details display its status as the baseline transfer is in progress.

3. Once the baseline transfer is completed, the IntelliSnap software adds the snapshots to the backup list, and the backup starts with the OCUM.

4. If SnapMirror is the destination copy, then the IntelliSnap software sends a command to update the mirror.

   The OCUM job is monitored and marked as completed/failed depending on the OCUM job status.

Why are my snapshots missing from the backup?

When backing up a snapshot of a client computer, ensure that the operating system of the backup server is either same or higher version than the client computer.

How are snapshots copied during a backup copy operation?

The snapshots are copied to media in a sequential order. If you wish to perform an inline backup copy operation and a previously selected snapshot has not been copied to media, the current IntelliSnap backup job will complete without creating the backup copy and you will need to create an offline backup copy for the current backup.

What should I take into account when using retention by number of jobs?

Configuring a storage policy or snapshot copy with job based retention is recommended for File System and File System like Agents, and not for Database Agents.

Review the following scenarios if you are using the retention by number of jobs configuration:

• During a browse operation, deleted files may be displayed for recovery. If the jobs containing these files are pruned by the retention criteria, the deleted files will be irrecoverable.

• You may need to manually delete jobs from deconfigured clients. These clients will continue to retain the old jobs since new jobs will not run again on them.

What UTF setting should be used for volume language?

To successfully browse and restore files on a NetApp file server that contain Unicode characters, it is recommended to use the UTF-8 setting for volume language. Please consult with NetApp for implications of changing volume language.

How is the OnCommand Unified Manager server affected when a snapshot copy is deleted?

If you delete a snapshot copy, the following components in the OnCommand Unified Manager server will be affected:

• The storage services associated to the snapshot copy will be deleted.

• Datasets associated with the deleted storage service will be deleted.

  Secondary volumes/datasets are not deleted as they are stored in case you need to perform a restore operation from a deleted dataset. Secondary datasets can be removed manually, if needed.

• Any relationship associated with a dataset will be deleted within a configurable period of time defined in the OnCommand Unified Manager server.

• Base snapshot copies remain available.

Is multi instancing supported?

No. Multi Instancing is not supported for IntelliSnap backup.

Can I use Media Explorer to restore data?

No. You cannot use Media Explorer to restore data. However, you can use the Media Explorer to restore IntelliSnap backup data from the backup copy.

How do I determine the number of streams to be used for a restore operation from a IntelliSnap backup?

For DB2, SAP for Oracle, and Oracle iDataAgents, when restoring from a snapshot using file system, the number of streams depends on the number of mount points used for the restore operation. Similarly, when restoring from a backup copy using file system, the number of streams depends on the number of media groups used for the restore operation.

How does Commvault select target devices during a clone or a snapshot operation?

When you configure an storage device using Array Management in the CommCell Console, the Device Group text box defines the target device group where Commvault will move the source and target devices during IntelliSnap backup operations. This option does not specify the source device group (from where a device should be found during Snap/Clone operations).

The following table explains the default behavior for selecting a Snap or Clone target device:

What happens to my backup if the timestamp on the CommServe and the client computer is different?

The incremental or differential backup will run as full backup and include all the files located on the source in the backup, even though these backups will be displayed as incremental or differential in the Job Manager.

Is IntelliSnap backup supported on volumes created on Windows Storage Space?

Yes, provided that the following considerations are taken into account:

• Storage Spaces are supported only on Windows 2012 or Windows 2012 R2

• The operating system of the proxy computer must be of the same or later version than the operating system of the source client computer

• For mount and unmount operations, the operating system of the destination client computer must be of the same or later version than the operating system of the source client computer

• If the storage pool contains any local disk, there is no support for IntelliSnap backup

• Use LUNs from the same engine to configure the storage pool

• if storage pool is configured, use the proxy computer to perform snap backup, backup copy, and restore jobs.